Hydroids and leptoids were first found in

Options

A. Liverworts
B. Hornworts
C. Mosses
D. All the above.

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks where hydroids and leptoids were first found. It provides four options: A. Liverworts, B. Hornworts, C. Mosses, and D. All of the above.

2. **Identifying the Plant Groups**:
- **Liverworts**: These are non-vascular plants belonging to the division Marchantiophyta.
- **Hornworts**: Another group of non-vascular plants, classified under the division Anthocerotophyta.
- **Mosses**: These belong to the division Bryophyta and are also non-vascular plants.

3. **Understanding Hydroids and Leptoids**:
- Hydroids are specialized cells that function similarly to xylem in vascular plants, helping in the conduction of water.
- Leptoids are similar to phloem and are responsible for the transport of nutrients.

4. **Analyzing the Options**:
- Since hydroids and leptoids are conducting tissues, they are specifically associated with mosses, which are known to have these specialized cells for nutrient and water transport.
- Liverworts and hornworts do not have these specific conducting cells.

5. **Conclusion**: Based on the information, hydroids and leptoids were first found in mosses.

**Final Answer**: C. Mosses

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